No band can help but reflect something of its audience during a live performance. Fortunately, Dervish, a hard-jamming pub band from County Sligo, Ireland, overcame the limitations of a straight-laced audience Sunday evening, converting a stubbornly passive crowd into a pack of whoopin' fans.

The band surely had its work cut out for it when the seven musicians walked onto the stage of the Leffler Center at Elizabethtown College, Lancaster County, Pa., because Lancaster County, it seems, just doesn't produce rowdy audiences. The members of Dervish seemed a little bewildered by the silence of the crowd during fast-paced, high-energy sets that would get most folks dancing in their seats.

Lead singer Cathy Jordan and the six lads in the band certainly seemed to be wishing the people who crowded into the fancy auditorium would move a little to the music, but except for some nodding heads and quietly tapping feet, the audience sat rock-still for much of the show. Jordan, stomping and swaying unceasingly to the music herself, kept peering out into the dark room as if worried that everyone had gone home.

Perhaps everyone was too enchanted by the music. Certainly the applause and cheers following every number -- and the way CDs disappeared during the intermission -- demonstrated the crowd's enthusiasm for Dervish's exuberant brand of Sligo traditionals. A brilliant fiddle, flute and accordian piece about 20 minutes into the show finally broke through the ice and the audience dared to clap along, finding the beat through sheer persistence. Once the restraints of recital hall etiquette were breached, the room livened up enough to hoot and holler with honest enthusiasm.

It takes a little rowdiness to appreciate a band like Dervish, which honed its art on Guinness-soaked stools in dark, crowded pubs back home in County Sligo. Jordan fronted the band with Irish charm and a voice sweet as honey mead. At the same time strong and delicate, Jordan's voice is a pure drop of Ireland, one of the best to come out of a country known for its singing.

She was unfortunately drowned out by the band during a few songs in the first half of the show, but sound problems notwithstanding, the seven-member band took full advantage of Leffler's grand acoustics and filled the rafters with sound. Alternating between blistering instrumental sets and songs sung in both English and Gaelic, the band seemed completely at ease on the stage, where Dervish ended a long tour Sunday before heading home to Ireland for a well-deserved rest.

Fiddler Tom Morrow and accordionist Shane Mitchell in particular made the music appear effortless, their fingers seeming to know by instinct exactly where and when to fall. While the others seemed to concentrate a little more on their playing, the music surely didn't suffer.

Dervish is one of the tightest, most balanced acoustic bands I've ever seen, overshadowing even an excellent performance by Ireland's hallmark band, the Chieftains, the previous evening in nearby Reading. Besides Jordan, Morrow and Mitchell, the band is Liam Kelly on flute and pennywhistle, Brian McDonagh on mandolin and mandola, Michael Holmes on bouzouki and Sheamie O'Dowd on fiddle and guitar. Jordan also played bodhran and bones, and kept up a charming banter between tunes.

"For God's sake, enjoy yourselves," Jordan told the crowd before the band launched into its first set of lively Sligo jigs. Once they loosened up enough to get into the spirit of the music, the audience took her words decidedly to heart.